feat: 添加数据库集成、定时任务调度器和事件Hook体系

- 新增数据库配置项(DB_TYPE, DB_HOST, DB_PORT等)，支持MySQL和PostgreSQL
- 集成GORM实现数据库连接和自动迁移功能
- 添加定时任务调度器(cmd/scheduler)，基于robfig/cron实现秒级调度
- 实现事件Hook体系，支持同步/异步处理和优先级排序
- 更新构建脚本，编译server、cli、scheduler三个二进制文件
- 配置systemd服务管理定时任务调度器
- 重构项目结构，新增crontab和hooks目录模块
- 更新README文档，完善各组件使用说明和部署配置

models/database/base_model.go

@@ -0,0 +1,11 @@
+package db
+
+import "gorm.io/gorm"
+
+// HostGroup 主机组
+type HostGroup struct {
+	gorm.Model
+	Name        string `json:"name" gorm:"not null;comment:主机组名称;index"`
+	Description string `json:"description" gorm:"null;comment:主机组描述;index"`
+	ParentID    uint   `json:"parent_id" gorm:"null;comment:父级ID;index"`
+}

models/database/init.go

@@ -0,0 +1,100 @@
+package db
+
+import (
+	"apiServer_service/utils/logger"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+
+	"gorm.io/driver/mysql"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+)
+
+var (
+	DB   *gorm.DB
+	once sync.Once
+)
+
+func ConnectDatabase() {
+	once.Do(func() {
+		dbType := os.Getenv("DB_TYPE")
+		dbUser := os.Getenv("DB_USER")
+		dbPassword := os.Getenv("DB_PASSWORD")
+		dbName := os.Getenv("DB_NAME")
+		dbHost := os.Getenv("DB_HOST")
+		dbPort := os.Getenv("DB_PORT")
+
+		if dbType == "" {
+			logger.Warn("Database", "DB_TYPE 未配置，跳过数据库连接")
+			return
+		}
+
+		var dialector gorm.Dialector
+
+		switch dbType {
+		case "mysql":
+			dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?charset=utf8mb4&parseTime=True&loc=Local",
+				dbUser, dbPassword, dbHost, dbPort, dbName)
+			dialector = mysql.Open(dsn)
+		case "postgres":
+			dbSchema := os.Getenv("DB_SCHEMA")
+			if dbSchema == "" {
+				dbSchema = "public"
+			}
+			dsn := fmt.Sprintf("host=%s user=%s password=%s dbname=%s port=%s sslmode=disable TimeZone=Asia/Shanghai search_path=%s",
+				dbHost, dbUser, dbPassword, dbName, dbPort, dbSchema)
+			dialector = postgres.Open(dsn)
+		default:
+			logger.Fatal("Database", fmt.Sprintf("不支持的 DB_TYPE: %s（仅支持 mysql / postgres）", dbType))
+			return
+		}
+
+		conn, err := gorm.Open(dialector, &gorm.Config{})
+		if err != nil {
+			logger.Fatal("Database", "连接失败: ", err)
+			return
+		}
+
+		sqlDB, err := conn.DB()
+		if err != nil {
+			logger.Fatal("Database", "获取底层连接池失败: ", err)
+			return
+		}
+		sqlDB.SetMaxOpenConns(50)
+		sqlDB.SetMaxIdleConns(10)
+		sqlDB.SetConnMaxLifetime(30 * time.Minute)
+		sqlDB.SetConnMaxIdleTime(10 * time.Minute)
+
+		DB = conn
+		logger.Info("Database", fmt.Sprintf("连接成功 (%s)", dbType))
+	})
+}
+
+func GetDB() *gorm.DB {
+	if DB == nil {
+		ConnectDatabase()
+	}
+	return DB
+}
+
+// Migrate 自动迁移所有模型，新增模型在此注册
+func Migrate() {
+	if DB == nil {
+		logger.Warn("Database", "数据库未连接，跳过迁移")
+		return
+	}
+
+	models := []interface{}{
+		&HostGroup{},
+	}
+
+	for _, model := range models {
+		if err := DB.AutoMigrate(model); err != nil {
+			logger.Error("Database", fmt.Sprintf("迁移 %T 失败: %v", model, err))
+		} else {
+			logger.Info("Database", fmt.Sprintf("迁移 %T 完成", model))
+		}
+	}
+}